Hello, is there a way to let some objects collide against a wall, and let other objects go through?
Thanks in advance!
I don’t know, but you can turn off collision on faces, maybe that helps. Also materials on objects prevent going trough meshes, I think you should play around with those settings. 
Not sure the application, also try making the object an actor and click the ghost button. If you leave collisions on in the texture face menu (F key, F9) then the object will register collisions but won’t bounce or interact off of them. So if you were making a fps, you could have the bullet pass through a wall but use a collision sensor to detect that it has hit an enemy on the other side and register damage. Or maybe a high powered laser that could cut through several enemies but couldn’t pass through a wall (same way, sense the collision, then do some action: end object, add explosion, etc.). Just another idea.
-Dvious
Sorry for the late response, I was kinda busy.
I think I need that material thing, but I’m not sure how to do that. Where can I find those settings? Thanks for the tip tho!
Well, I need some sort of disc to only be able to be in a certain area, to pushs other discs off his area. So I don’t know if that’s possible with ghost settings, cos won’t he slip through the floor as well, then? But thanks anyways for the reply.